Process of preparing merchantable iron from tin-plate scrap.



E. A. SPERRY. PROCESS OF PREPARING MERGHANTABLE IRON FROM TIN PLATE SGRAP.

APPLICATION FILED APR.11, 1908.

E. A. SPERRY. PROCESS OF PREPARING MERGHANTABLE IRON PROM TIN PL'ATE SCRAP.

APPLIOATIQN PIL ED=APR. 11 1908.

Patented Dec. 8, 1908.

3 SHEETSSHEET Y INVENTOR v E. A. SPERRY. PROCESS OF PRBPARING'MERGHANTABLB IRON PROM TIN PLATE SCRAP.

' APPLICATION FILED APR. 11, 1908. 906,321. Patented Dec. s, 1908.

s SHEETS-SHEET s.

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Allorlzgw,

ELMER A. SPERRY, OF BROOKLYN, NEW YORK.

s'ra'rs PROCESS OF PREPARING MERGHANTABLE IRON FROI i TIN-PLRTE SCRAP.

" i No. 906,321.

Specification of Letters Patent.

Patented Dec. 8, 1908.

Application filed April 11, 1908. Serial No. $26,613.

'-1oall whom it may concern:

Be it known that I, ELMER A. SPERRY, a citizen of the United States, residing at :fBrooklyn, in the county of Kings and State of New York, have invented new and useful Improvements in Processes of Preparing Merchantable Iron from Tin-Plate Scrap,

' of which the following is a specification.

"This invention relates to the preparing of merc'hantable iron from tin plate scrap and it consists in treatment both prior to and after the detinning step proper which is calculated to better lit the scrap for merchan- "dising and also for furnacing'. The detinning step in connection with this invention may be suitably formed by any well-known process but. it is understood that the preferred process for thedetinning step is based '7 on the chemical reaction between chlorin and nietallictin which produces stannic chlorid. Tin'o'r any tin bearing material,

such for instance as tin plate scrap may be iconsidered as suitable for thesupply of the metal.

The tin scrap shipped in open cars when apparently dry, usually contains about 1% of moisture, and at the same time contains 'less than 2. of tin. The prior treatment and especiallythe careful drying of the tin bearing material or scrap before the reaction, becomes therefore extremely desirable. Inasmuch as the present process, though not limited thereto, contemplates the use of 'i'noistchlorin and is enabled to produce 951 of tin product in the anhydrous form, the, importance ofsthe preparatory steps of both the reagent and the tin bearing material "itself will atonce become apparent.

When reclaiming the values from tin scrap as for instance by making the chlorin scrap contain- 'ing about 217% of tin, the heat genera vated is sufiicient to raise the scrap as a Whole, including the steel late with spe 'cific heat of .1 to a very hig temperature, unless the heat of the reaction is. absorbed.

' Whereas dry chlorin or moist chlorin in the presenceof anhydrous stannic chlorid does not attack steel,yet owing to the zone where the tin and steel are alloyed, the complete removal of the tin, which can only be accomplished by'chlorin so far as known, leaves "this zone in a spongy state with agreat 'many minute particles of iron resting upon the surface of the black scrap, which are usually converted into halogen compounds of iron.

The invention further relates to the preparation of both the tin bearing material or tin scrap before it is reacted upon, and a prior treatment of the reagent itself for purposes of better fitting it for these reactions. The treatment of the scrap prior to detinning consists in part in cleansing the scrap from foreign substances, such asfats, oils, comestibles, and also from metals other than tin, including solder, antimony, etc., also the preparation of the tin scrap both prior to and after billeting, or. compacting into bundles.

It further consists in cooling during reacting period or reacting under conditions of temperature control and also such condi tions of internal stress and pressure as are calculated to open up the interstices of the scrap to .allow better penetration, heating the scrap to quite a high degree to dry same, treating the reagent and reacting .upon same while hot, or before allowing the scra to cool, reclaiming the tin bearing, pro ucts either as liquid, solids, gases or vapors, and also in further treatment of the resulting black scrap, whereby'it is first freed from the reagents or products of the reaction and afterward is rendered fit for the market, and also a special treatment is given to fit this scrap for furnacing.

The process consists in the prior treatment, bundling" or compressing the scrap to' a point best suited for the dctinning step. If this is found too loosely compacted for furnacing or where the opening up of the compacted scrap during the process or any of t e steps is excessive or where for any reason the resulting black scrap is not found to be sufiiciently dense for the metallurgical or iron working processes to follow; the billets or bundles are re-compacted or supercompressed' by any of the well-known methods as by hammering, or, for instance by the use of the press shown and describe as will be readily understood. This part of the process consists in compressing, bnndiing or billeting the scrap in two stages, between which occur the other steps constituting the process. These may or may not be accom panied by changes in temperature, mechantrifugal action or other phenomena hereinafter described. A novel and useful techical stress for opening up the scrap, .cen-

'nical feature is thus secured in hastenin the reaction and treatment in other steps the process, through the oomparativeopenness of the scrap which is com ressed, and at the same time being capabe of delivering black scrap compacted to the high degree re uired by the metallurgist.

ther details are described in the specification, illustrated in drawlngs and pointed out in the claims forming a part hereof.

Referring now to the accompanying drawings which, are employed simply as illustrating one. inethodof carrying out my invention and in which the reference characters indicate similar parts throughout: Figure 1 shows the're-compactin or supercompressing hammer for the bil ets. Fig. 2

illustrates the saponiiication and washing.

apparatus. F i 3 illustrates the de-soldering furnace an mangling or dismembering apparatus in diagram. Fig. 4 is a diagrammatic view of a billeting press. Fig. 5 illustrates one of the laminated billets. Figs. 6 and 7 are the details of the perforated cylindrical retainer. Fig. 8 is detail showin the skeleton of the shaft with its revol ving p'arts. Fig. 9 illustrates the method of handling one of the retainers. Fig. 10 is a view of the reaction chamber with the tin billets in place therein, invertical section. Fig. 11 is an exterior view of the reaction vessel together with one of the condensers and 33 (Fi 2), the container carrying the scrap handle by crane 34. This vessel may or may not be heated by furnace 35. Reservoir 33 contains caustic alkali or a compound 'COIltaining free alkali, and serves to saponify fat, filth and comestibles clinging to the scrap, especially to old scrap. After saponification in vessel 33 the container is suitably washed and rinsed, as in vessel 36, from whence it may pass to the desoldering apparatus shown in Fig. 3. Here the scrap 44 is made to passthrough a highly heated zone as in cylinder 37 within thefurnace 38, provided with stack 41. The scrap may be fed by hopper--39 and issues through the educ'tion tube 40.

i so

The scrap, either before or after. being desoldered, preferably the latter, and either While hot or after beingcoo'led, is passed through the manglingrolls 42 'and'43,run mug in opposite directions and preferably at differential speeds This serves to dismember mangle or shred thescrap and pre pare it more easily for the next step in the process, namely, the pressing, compacting or per 51 on its backward stroke and hold same closed on its forward stroke. WVhen back, a

small mass of the scrap; 45"is thrown in front of the plunger 50 and added to the billet '52 successively,until same is completed, whereupon a septum, as for instance a sheetiron plate, is drop ed'into place to The resist- 'ance to theforward movement of; the line of billets 52 -52, &c..is obtained through completely-separate the b1 ets.

lateral pressure of the springs 5353 &c. which press upon one or more sides ofthe billet through the medium of flexible walls 54 of the rectangular tubular extension in front of the ram or plun er 50 and from the far end of which the billets'52 gradually issue. It will be noticed that these billets are laminated flatwise through the successive additions of portions or layers 52, '52 &c. and also that the billets themselves are preferably rectangular and fiat, as shown in Figs. 4, 5 and 10; but any shaped billet may of course be employed' The billets 52 are now introduced into the process proper,

either direct or after undergoing tfurther When used, this p're-trea'tpre-treatmcnt.

ment consists in the steps n'esently to be explained. Circular tubs or retainers 55 are provided with a floor 56 perforated with a large cen- I tral opening 57' the periphery of which consists of perforated meta'l as shown in Fig.

'6 and indicated at.58. Interior to this retainer are internal radial ribs 59 perforated at their upper ends at 60 and serving to'afct as handles to the retainers and guides for the billets 52 as indicated in Fig. 7. Inter- 'mediately disposed are tubular extensions 61 which register with four equidistant Openings 62 in the floor of, the retainer. Into this basket are placed billets 52 to the height of, say, five, 'one uponthe other, 40 in all, and leaving a central s ace or open *ing 57' the retainer as a whole eing handled I by a crane, as shown in Fig. 9 with the hooks 63 engaging the openings 60 in the plate 59. For rece tit m of a number of these retainers say. five as is shown in Fig. 10, thereis a framework consisting of a central sha- 65 consisting of radialarms 66 andbrace. 67 engaging the shaft 64 by webs 68 an 64 provided at its lower extremity withaspider serving to hold the ring 69 in which are located the graphite blocks 70 serving as a chemically inert journal or guide for the lowerend of this organization. At the extremity of each of the radial arms are the tubes or bars 70 serving as vertical guides for the retainers and cooperating with the openings therein, the spider 71 at the top being removed while the retainers are being slipped upon the guides or tubes 70, by means of the crane device shown in Fig. 9. After the last basket is ill position, the spider 71 is placed over .the tops of the guides 70, thus fixing their upper ends with reference to the central shaft. 64. Hanger 72- slips over the end of the shaft simply for the purpose of handling the group of retainers as a whole by chains 73 and key 74. A similar key 74 is used at the bottom of the shaft for securmg and hanging the spider 65. The assembled retainers being now secured to the shaft, it may be lowered into any one of the chambers provided for its reception where the scrap may be washed, treated or dried, or where it is dried and heated, or the chamber 75, jacketed as shown at 76, Fig. 10 provided with a stationary upward projection of its bottom tube 77 perforated for draining at 77, on the outside of which the graphite blocks 7 0 impinge, acting in their capacity as guide and journal. It should be remembered that the load is perfectly supported through the shaft 64, by the ball bearing 78 on the top of gland 7 9, forming a part of the .35 cover 80 of the vessel. This ball thrust bearing may be plainly seen in Fig. 11 as being under the flanged pulley 81, the key 74: being now used as a driver as well as hanger be tween pulley 81. and the shaft 64. The organization is such that a small amount of power applied to pulley 81 will revolve the mass within the chamber 75. The ends as well as 'the sides of this retainer may be jacketed as indicated at 82 at the bottom and an .eduction passage is provided preferably at the top indicated by passage 83, and preferably also tangentially disposed asindicated in Fig. 16.

Referring now to Fig. 11, the exterior of the vessel 75 is shown with its eduction passage 83 and cover 80 attached as by quickly operating cams 85 operating in slots on the cover in the well-known manner. Means for heating this vessel are shown at 85, and for cooling the vessel shown M86 and also 87 being a valved sight discharge into funnel 88. The reagent reaches thevessel'through the smaller pipe 89 and'traverses jacketed.

valve 90, thence upwardly into the reaction vessel 75, out through another valve 91, preferably jacketed and connected to the disgharge opening,each of these valves being piped to the respective ends of the cooler or condenser 92 which is also provided with as heating means 85 and cooling means 86, and

also with a similar valved sight-discharge apparatus 87 and S8. The condenser 92 is suitably jacketed as is preferably also the pipe 93 leading from its upper end and connecting with valve 94 and separator 95, the top of the separator being connected by jacketed discharge pipe 96 with the tower or scrubber 97. The passage 98, preferably jacketed for temperature control, serves to connect valve 90 with the lower end of the condenser or cooler 92 and is provided with a discharge opening for liquids or products indicated at 99. Trapped as shown at 99. The valve 90 is shown in section in Figs. 12 and 13, the upward discharge being connected simultaneously with the jacketed pipe 98 and also with the chlorin supply pipe 89, the flow of the gases being indicated by the arrows, the moving part of the valve 100 serving to connect the reaction chamber 75 with the various passages which are designated on the drawing. The condensers may be two in number, only one of which is connected with the reaction chamber at'a time, but in each instance the chlorin connection 89 is uninterrupted. But both passages 98 and 89 are interrupted when the communication is made with the hot air passage 101. The valve is suitably drawn and held to its seat as by springs 102 and operated by a stem 103. The valve 91 is indicated in section in Fig. 14, and its central chamber may be put in communication, one at a time, with any one of the L passages shown in said figure. -Valve serves to establish communication between the separator 95 and one or the other of the condensers 92 by pipes 93-93, or its revolving part may be so turned as to stop off all com-' munication with either of the condensers.

Prior to the introductiongof the load of scrap into the chamber 75 it is preferably heated and thoroughly air-washed in any suitable inclosure, such as for instance an oven or furnace, preferably under conditions of centrifugal stress which opens up the interstices thereby facilitating heating and drying. Prior to its introduction to the oven orfurnace, the scrap after being packed into the baskets and the baskets assembled, they may be lowered into a washing tank and there washed and afterward rinsed, should they be found to require this treatment. After they have been introduced into the tank 75, the valves 90 and 91 may be so adjusted as to communicate with any suit able source of hot air and may be again airwashed, either quiescent or. while spinning, and under conditions of centrifugal stress, all prior to the step of detinning. The pressures in. this case, as will be seen, are all applied substantially parallel with the laminae 52 of the bundles. In connection with drying, the scrap may also be heated and cooled, which in and of itself tends to open up the so which the bundle 52 interstices of the compacted scrap to a. re-

markable degree and thus facilitate the drying. After the reaction is com leted, the scrap is then heated to a high e 'ee and may be thenor afterward, air-was ed with heated air, all under conditions of centrifu- 'al stress or change in centrifugal stress, for removing the last trace of both the re agent and the product. The remaining black scrap now goes to a suitable chamber 111 after the reaction and the separating treatment above described in the reaction vessel 75. Here it is Washed free of any remnant of the reagent or products, and treated with a suitable nonrusting material, or compound, such for instance as caustic alkali. The group of retainers are then dismembered. Each retainer is in turn lifted from its position around the shaft, and the billets removed fromthe retainers, as by dumping, and the retainers refilled, and the process repeated. The billets dumped from the retainers have been subjected to considerable stress 'inopening up their interstices or, if-

I for any other reason they require re-packing or super-compressing this may be accomplishedby the hammer shown in Fig. 1 which is of the ordinary construction and consists of the hollow base, ordye 20 on may be seen'and which is adapted to receive the heavy platen 25, su ported on the piston 24, drivenby the cy inder 22, which is supplied with steam" I chest 26 and steam pipe 27 and is supported from, jthe base by the arm 21. suitable f rm of hammer or compressing apparatus may bee'm ployed as for instance those shown in Fig. 4 where the springs 53 may be adjusted to oifer more than normal resistance to-the billets 52 which may thus be re-compressed or super-compressed, as will be readily understood.

The use and operation of this apparatuswill be readily understood from the foregoing description. It may, however be pointed out that the tin-bearing material,

h such preparation as is necessary is treate inthe reaction vessel '75 preferably .under conditions of centrifugal stress by the rotation of the assembled'retalners, upon the axis 64, the perforated cylindrical walls of junction with the retainers and radially exposed billets of scrap, together with the radial plates 59 and also the radial web's 68, all acting in conthe large central openin' 57' produce a definite fan action and t row the fluidsvigorously toward the outer wall discharge opening 83.

of the vessel 7 5 the gases and vapors and also ing moisture, ultimately e tangentially disposed the heated-air carr passing through t It will be 'readily' understood that the scrap treated by this process need not be bil- Any other .4 wherein the springs '53. for instance the tin scrap, after having gone throu ,pacted or super-comlpressed, rendered more sulta billets by a comparatively slow rotative speed of the retainer about the shaft 64. This organization requires practically no power except for overcoming the inertia, inasmuch as the Whole load is borne by the ball bearin seen in Fig. 11 below pulley 81. It will further be noticed that the centrifugal stress thus developed is unilinear, in direction and is at right angles to the line of the thickness of the billets and also at r i ht angles to the line of pressure applied in tile com actin of the billets, and furthermore in ine with the laminations 52 within the. billets, whereby the interstices of the compacted scrap are opened up vigorously for the entrance of the reagent, removal of the product for the heating both before and after the reaction, for the drying off of the product and for the impregnation 'of the mass bythe alkali described. i

The preliminary treatment of both the reagent and the tin scrap has been variously described by'me in this art and need not further be pointed out here, except ,to mention that the tin-scrap, especially old tin scrap, should be dismembered and man led or shredded, not only for purposes 0 better attack bythe reagent, but for purposes ofconstructing billets which will more readily cohere and not readily disintegrate nder 1n ayers' the conditions of being compile or by separately added ortions. Especially is this true when-the illets have not been compacted as densely as possible before the reaction and are then and centrifu al pressures which tend to open them up and render necessary the re-comactin or super-compressin of such bunles a ter the ste of detinning and. cleansing of the scrap has been completed. This recompacting may be done by any suitable machine, as for instance that sliown in Fig. may be adjusted for greater compression and the billets one placed under stresses after the othersub'ected-toheavier pressures than formerly or t e recompactin or su ercompressing may be accomplishe ing the bundles under the hammer shown in Fig. 1 where they are very viggrousl coming t ereby 1e for furnacin the billets after having been compressedfiieihg removed in' any suitable manner, as for'in-v stance through the bottom of the dye in the base20 of the hammer. I

Having pointed out the esscntialfeatures of my process or method of producing halogen com ounds of tin, I may state that the process s ould not in any way be limited to theexact details of'thermethod or apparatus described herein withreference to any parby p ac others may be employed, and the invention extends to such use.

,I'claim:

1. Ihe process of preparing merchantable iron from tin plate scrap which consists in compacting the scrap in laminated bundles,

- treating the bundles with mechanical stress in line of the laniinations, for opening up the interstices of the bundles, for the purpose specified and recompressing such bundies at right-angles to the laminations.

2. The process of preparing merchantable iron from tin plate scrap which consists in suitably treating the scrap and mangling same, treating witha reagent capable of re-, moving the-tin separately recovering. the resuiting black scrap and the tin bearing products and compacting the former into coherent bundles. 1

3,; The'process of preparing merchantable iron from tin plate scrap which consistsin compacting'the scrap at an elevated temperature, into bundles, suitably treating the scrap forremoval of the tin and recompressing the said bundles.v

4c. The process of preparing merchantable iron from tin plate-scrap which consists in compressing the scrap into bundles, treating samewith a reagent for the removalofthe tin, removing the products thus produced by centrifugal action "and recompressing the i V scrap.

5. The process of preparing merchantable iron fromtin plate scrap which consists in compressing the scrap into bundles, treating the scrap with ade-tinning reagent, heating thesame-under conditions of centrifugal action and recompressing the scrap.

6. The process of preparing merchantable I iron'irom tin plate scrap which consists in sapon'ifying and washing the scrap, billeting same, heating the billets to drive off moisture, treat-ing with; a reagentcapable of recovering the tin and separately recovering the resulting black scrap and the tin bearing ,products.

7. The processof preparing m erchantable iron from tin plate scrap which consists in saponifying and mangling the scrap, bun- (lling same, treating with a reagent capable of removing the tin, separately recovering the resulting black scrap and the tintbearing products and recompressmg the said bundles.

bundles by pressure applied at 8. Theprocess of preparing merchantable iron from tinplate scrap which consists in drying the scrap, bundling same, treating. with a reagent capable of removing the tin,

separately recovering the resulting black scrap and the tin bearing products and recompressing the said bundles.

9. The process of preparing merchantable iron from tin plate scrap which consists in drying the scrap at an elevated temperature, billeting same, treating with a reagent capable of removing the tin and separately recovering the resulting black scrap and the tin bearing products, and recompressing the said billets.

10. The process of preparing merchantable iron from tin plate scrap which consists in de-soldering the scrap, billeting same,treating with a reagent capable of removing the tin and separately recovering the resulting black scrap and the tin bearing products, and recompressing the said billets.

11. The process of preparing merchantable iron from tin plate scrap which consists in de-solderin'g and mangling the scrap, billeting same, heating the billets to drive off moisture, treating with a reagent capable of removing the tin and separately recovering the resulting black scrap and the tin bearing products.

12. The process of preparing merchantable iron from tin plate scrap which consists in saponifyingand then de-soldering the scrap, bi let-ing same, treating with a reagent capable of removing 'thetin and separately recovering theresulting blackscrap and the tin bearing products, and recompressing the said billets.

13. The process offpreparing merchantable iron from tin plate scrap which consists in vcompacting the scrap in bundles by pressure,

the bundles being relatively thin along the line at which the pressure 'is applied, treating with a reagent capable of removing the tin separately recovering the resulting black scrap and the tin bearingproducts and recompacting the bundles by pressure applied along the line of the original pres tires.

14. The process of preparing me charitable iron from tin plate scrap which consists in compacting the scrap at an elevated temperature in bundles by pressure, treating with a reagent capable of removing the'tin and separately recovering the resulting black scrap and the tin bearing products.

15. The process'of preparing merchantable iron from tin plate scrap. which consists in compacting the scrap in laminated bundles by pressure, treating witha reagent capable ofremoving the tin separately recovering the resulting black scrap, and the tin bearing products and recompacting the right angles to the lainlnations. a

16. The process of preparing merchantable iron from tin plate scrap which consists in compacting the scrap in laminated bundles by pressure, the laminations being at a substantial angle to the line at which the pressure is applied, treating with a reagent capable of remo'ing the tin and separately recovering the resulting black scrap and the tin bearing product and recompacting the bundles by pressure applied along the line of the original pressures.

17. The process of preparing merchantable iron from tin plate scrap which consists in compacting the scrap in laminated bundles, the bundles being relatively thin, the laminations being flatwise of the bundles, treating with a reagent capable of removing the tin and separately recovering the resulting black scrap and the tin bearing products.

18. The process of preparing merchantable iron from tin plate scrap which consists in compacting the scrap in bundles by a plurality of separate additions of scrap compacted under pressure, cbnstituting laminations within the bundle, treating with a reagent capable of removing the tin and separately recovering the resulting black scrap and the tin-bearing products.

19. The process of preparing merchantable iron from tin plate scrap which consists in billeting the scrap, packing the billets into retainers, subjecting the group of billets thus packed to a suitable preliminary treatment for the purpose of drying same prior to de-tinning, then treating with a reagent capableof removing the tin and separately recovering the resulting black scrap and the tin bearing products.

20. The process of preparing merchantable iron from tin plate scrap which consists in billeting the scrap, packing the billets into retainers, heating the group of billets thus packed, treating with a reagent capable of removing the tin and separately recovering the resulting black scrap and the tin bearing products.

21. The process of preparing merchantable iron from tin plate scrap which consists in billeting the scrap, packing the billets into retainers, treating the group of billets thus packed with hot air, treating with a reagent capable f removing the tin and separately recovering the resulting black scrap and the tin bearing products.

22. The process of preparing merchantable iron from tin plate scrap which conin billeting the scrap, packing the billets into retainers, treating the group of billets thus packed with heat to dry same and facilitating the escape of moisture from the interstices of'the billets by opening up the mass while thus heating, treating with a re: agent capable of removing the tin and seping, treating with a reagent capable of removing the tin and separately recovering the resulting black scrap and the tin bearing products.

" 24. The process of preparing merchant able iron from tin plate scrap which consists in billeting the scrap, packing the billets into retainers, treating the group of billets thus packed with heatto dry same and interstices of the billets by opening up the mass by pressure independent of the pressure of the surrounding media, while .thus heating. treating with a reagent capable of removing the tin and separately recovering the resulting black scrap and the tin bearing products.

25. The process of preparing merchantable iron from tin plate scrap which consists in billeting the scrap, packing the billets. into retainers treating the group of billets thus packed with heat to dry same and facilitating the escape of moisture from the interstices of the billets by opening up the mass in the presence of a moving gaseous medium while thus heating, treating with a reagent capable of removing the tin and separately recovering the resulting black scrap and the tin bearing products' 26. The process of preparing merchanta.b l e iron from tin plate scrap which consists able iron from tin plate scrap which consists in billeting the scrap, packing the billets into retainers, placing the retainers within a suitable inclosure, applying pressure and causing a current of gas to flow within the inclosure for drying same, treating with a reagent capable of removing the tin and separately recovering the resulting black scrap' and the tin bearing products.

28. The process of preparing merchant- Lat le iron from tin plate scrap which consists facilitating the escape of moisture from the 27. The process of preparing merchant in billeting the scrap, packing the billets into retainers around a central space and dryingthe scrap by causing a flow of gas developed by rotating the retainer so packed, treating with a reagent capable of removing the tin and separately recovering theresulting black scrap and thet-in bearing prod,- ucts.

29. The process of preparing merchant. able'iron from tin plate scrap which consists in billeting the scrap, packing the billets into retainers around a central space and drying the scrap by causing a flow of gas developed by rotating the retainer so packed, heating the scrap, treating with a reagent capable of removing the "tin and separately recovering the resulting black scrap and the tin bearing products.

30. The prmess of preparin merchantable iron from tin plate scrap which consists in billeting the scrap, packing the billets into retainers around a central space, placing the retainers within achamber provided with a central induction and a peripheral eduction opening and drying the scrap by flow of fluid established by rotating the retainer, heating the group of billets thus packed, and treating with a reagent capable of removing the tin.

31. The process of preparing merchantable iron from tin plate scrap which consists it in packing the scrap into bundles, suitably treating the scrap for removal of the tin and recomprcssing the scrap.

32. The process of preparing merchantable iron from tin plate scrap which consists in billeting the scrap, packing the billets into retainers around a central space, placing the retainers within'a chamber provided with suitable induction and eduction opening and developing a fluid current from the central space outwardly through the scrap for drying same, then, treating with a reagent capable of removing the tin and separately recovering the resulting black scrap and the tin bearing products.

The process of preparing merchantable iron from tin plate scrap which consists in compressing the scrap into bundles, detinning with a-reagent, treating the scrap with centrifugal action during detinning, for the purpose of effecting quicker penetration of the bundles by the said detinning reagent and recompressing the scrap.

34. The process of preparing merchantable iron from tin plate scrap which consists in billeting the scrap, packing the billets into retainers, heating the grouplof billets thus packed under the combined condition of How of gases through the scrap and centrifugal action, treating with a reagent capable of removing the tin and separately recovering the resulting black scrap and the tin bearing products.

i The process of preparin merchantable iron from tin plate scrap w iich consists in compressing the scrap into -flat billets, packing the billets flatwise into circular rows, suitably preparing the scrap so packed and treating same with a reagent capable of removing tin causing the fluids to flow through said scrap by centrifugal action separately recovering the resulting black scrap and the tin bearing products.

36. The process of preparing merchantable ii n1 from tin plate scrap which consists in compressing the scrap into laminated billets, packing such billets to form a cylinder with the laminations in a plane normal to the axis, suitably preparing the scrap so packed causing the fluids to flow through said scrap by centrifugal action treating same with a reagent capable of removing tin and separately recovering the resulting black scrap and the tin bearing products.

37. The process of preparing merchantable iron from tin plate scrap which consists in compressing the scrap into flat billets, packing the billets flatwise into a cylindrical retainer, the plane of the billets being normal to the axis treating same with a reagent capable of removing tin causing the fluids to flow through said scrap by centrifugal force and separately recovering the resulting black scrap and the bearing products.

38. The process of preparing merchantable iron from tin plate scrap which consists in compressing the scrap into laminated billets, packing such billets within a cylindrical retainer with the laminations in a plane normal to the axis, causing the fluids to flow through said scrap by centriitugal force treating same with a reagent capable of removing tin and separately recovering the resulting black scrap and the tin bearingproducts.

39. The process of preparing merchant able iron irom tin plate scrap which consists in com pressing the scrap into bundles,treating the scrap with heated gas, under centrifugal action for hastening the heating and drying of the scrap, prior to detinning, detinning the scrap and then recompressing the bunscribed, and then recompressing the scrap.

the interstices in the bundles for hastening the action during detinning as de- 42. The processof preparin merchent- In testimony whereof I have hereunto set able iron from tin plate scrap w 1ic11 consists my hand in presence of two subscribing witi n compressing the scrap intobundles, denesses.

iiimin with a reagent,- treating the scrap vmh ifi'ering temperatures during detinmnfifor. the purpose of quicker penetration Witnesses: ofit re bunci les by the said detinning reagent, A. MATTULLATH, and rccomp'ressing the scrap, FRANCIS O. PA UST.

ELMER A. SPERRY. 

